Buddypress v5 : comment feature for post

In my site, There is no comment option available for post type activity. For all other activity it shows comment option. From buddypress setting, comment option is also enabled. I tried by changing theme to twenty twelve and deactivating all plugin except buddypress My site : https://twolyn.com/ Front page is activity page. If you scroll down you will see post, But no comment option.
Let me know what i am missing, Or any code should i add